1. Field of the Invention
This invention relates to a method of making dry toner powders for photocopying machines.
2. Background Information
In the process for the manufacture of dry toner powders for photocopy machines, those which comprise a thermoplastic organic resin and magnetic powder are difficult to make because a high shear is needed to blend the components homogeneously. There is thus a need to find a method to improve the handling or processing of the toner. The present invention is a method of providing the toner without the use of the high shear resulting in a product which is a completely satisfactory homogeneous blend.
Keil in U.S. Pat. No. 3,511,788, issued May 12, 1970, teaches using a copolymer of SiO.sub.2 units and units selected from the group consisting of (CH.sub.3).sub.3 SiO.sub.1/2 and Q(CH.sub.3).sub.2 SiO.sub.1/2 units, wherein Q is a radical containing a solubilizing group and the ratio of SiO.sub.2 units to the total (CH.sub.3).sub.3 SiO.sub.1/2 and Q(CH.sub.3).sub.2 SiO.sub.1/2 units is in the range of 1/0.6 to 1/1.2, to mix with organic liquid or plastisol to make a foam. Keil is concerned with liquid systems and foams which are different from the dry toner powders of the present invention.